#include <cstdio>

typedef long double ld;

ld get(ld x,ld c){
	return x>=1 ? 1 : 1+(1-x)*get(x+c,c);
}

int main() {
    freopen("lol.in", "r", stdin);
    freopen("lol.out", "w", stdout);

    ld x;
    scanf("%LF", &x);
    printf("%.10LF", 1/get(x/100, x/100));
    return 0;
}
